In recent years, larger display devices have been required. Examples of uses for a large display device include a television device for home use (also referred to as a TV or a television receiver), digital signage, and a public information display (PID). A larger display region of a display device can provide the increased amount of information at a time. In addition, a larger display region attracts more attention, so that the effectiveness of the advertisement is expected to be increased, for example.
In addition, for application to mobile devices, larger display devices have been required. In recent years, browsability has been considered to be improved by increasing the amount of information to be displayed at one time with an increase of a display region of the display device.
Light-emitting elements utilizing EL (also referred to as EL elements) have features such as ease of thinning and lightening, high-speed response to input signal, and driving with a direct-current low voltage source; therefore, application of the light-emitting elements to display devices has been proposed. For example, Patent Document 1 discloses an example of a display device including an organic EL element.
Furthermore, Patent Document 2 discloses a flexible active matrix light-emitting device in which an organic EL element and a transistor serving as a switching element are provided over a film substrate.